It’s been quiet on the Lync Validator front for a while but it’s not because we have been slacking off or no one is using the site.  A quick peek at the stats show that we have scanned nearly 4000 ports, nearly 8000 DNS checks and are closing in on 1,000 saved deployments.  And I promise, it’s just going to get better.

What’s New?

So there are a few changes that are worth mentioning to the application and are going to be featured here.

Services In Azure

From the very start we have been hosting the SQL Backend of LyncValidator in Azure but with this update comes the front-end application as well.  If you have never heard of Azure (and apparently you are living under a rock but have internet to read this post), I believe it might be the single best collection of online tools ranging from SQL, Web Hosting and much more.  I would love to say that I’m getting paid to make such an endorsement but sadly I am not.  What this change does mean however is that we will increase our uptime from the server that was being hosted in Azure instead of my house.

UDP Service Checks

Up to this point, the LyncValidator was only doing a single UDP check for service availability.  With this update, we introduce the ability to do a UDP Service check against the Edge Server.  Checking if a UDP port is open isn’t as simple as doing a port query, like it is with TCP.  Instead, UDP is a connectionless protocol which means in order to check something, we need to send the application a request, wait for a reply and inspect the reply coming from the query.

In order to accomplish this, I wrote a quick web service which took a request to allocate a media port and passed it to the edge server.  The Edge Server rejects my request as I don’t have the proper permission to do an allocate request but the fact that I get a rejected message back from the server confirms that not only is port 3478 listening but that the AV Service is running on the server.

Bug Fixes & Improvements

Fixed two situations in which the HOSTS file creation for the edge server would include only the pool names but not the front-end server names themselves.  Although not strictly required I’ve seen plenty of situations where the edge server has issues if the pool name isn’t in the HOSTS file so we will add it now.  Also, updated the reverse proxy HOSTS file to include the external web services name as some reverse proxy solutions (i.e. IIS/ARR) will require that.

But don’t worry – over the coming months there will be even more changes.